RESUMO
BACKGROUND: The utility of pressure waveform analyses to assess pulmonary vein (PV) occlusions has been reported in cryoballoon PV isolation (CB-PVI) using first-generation CBs. This prospective randomized study compared the procedural and clinical outcomes of pressure-guided and conventional CB-PVI. METHODS AND RESULTS: Sixty patients with paroxysmal atrial fibrillation underwent CB-PVI with 28-mm second-generation CBs. PV occlusions were assessed either by real-time pressure waveforms without contrast utilization (pressure-guided group) or contrast injections (conventional group) and randomly assigned. Before the randomization, 24 patients underwent pressure-guided CB-PVIs. In the derivation study, a vein occlusion was obtained in 88/96 (91.7%) PVs among which 86 (97.7%) were successfully isolated by the application. In the validation study, the nadir balloon temperature and total freezing time did not significantly differ per PV between the two groups. The positive predictive value of the vein occlusion for predicting successful acute isolations was similar (93 of 103 [90.2%] and 89 of 98 [90.8%] PVs; P = 1.000), but the negative predictive value was significantly higher in pressure-guided than angiographical occlusions (14 of 17 [82.3%] vs 7 of 22 [31.8%]; P = .003). Both the procedure (57.7 ± 14.2 vs 62.6 ± 15.8 minutes; P = .526) and fluoroscopic times (16.3 ± 6.4 vs 20.1 ± 6.1; P = .732) were similar between the two groups, however, the fluoroscopy dose (130.6 ± 97.7 vs 353.2 ± 231.4 mGy; P < .001) and contrast volume used (0 vs 17.5 ± 7.7 mL; P < .001) were significantly smaller in the pressure-guided than conventional group. During 27.8 (5-39) months of follow-up, the single procedure arrhythmia freedom was similar between the two groups (P = .438). CONCLUSIONS: Pressure-guided second-generation CB-PVIs were similarly effective and as safe as conventional CB-PVIs. This technique required no contrast utilization and significantly reduced radiation exposure more than conventional CB-PVIs.
